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71.
T Eguchi N Ikekawa K Sumitani M Kumegawa S Higuchi S Otomo 《Chemical & pharmaceutical bulletin》1990,38(5):1246-1249
A series of analogs of 1 alpha,25-dihydroxyvitamin D3 [1,25-(OH)2D3 (1)] with alkyl substitutions in 26- and 27-positions have been tested for their activity 1) in competing with 1,25-(OH)2D3 for binding to chick intestinal cytosol receptor, 2) in ability for formation of multinucleated cells (MNC) with various osteoclastic cell characteristics from blast cells, and 3) in stimulating bone calcium mobilization in vitamin D-deficient rats. The relative potencies of 1,25-(OH)2D3, 1 alpha,25-dihydroxy-26,27-dimethylvitamin D3 (2), 1 alpha,25-dihydroxy-26,27-diethylvitamin D3 (3), and 1 alpha,25-dihydroxy-26,27-dipropylvitamin D3 (4) in competing for intestinal cytosolic binding were 1:1.1:0.25:0.05. The similar order of the abilities on formation of the multinucleated cells in the same series was observed. In a bone calcium mobilization test with vitamin D-deficient rats, 1 alpha,25-dihydroxy-26,27-dimethylvitamin D3 showed slightly less activity than 1,25-(OH)2D3 at 12 h after administration, but long lasting activity was observed during time course experiments. 1 alpha,25-Dihydroxy-26,27-diethylvitamin D3, and 1 alpha,25-dihydroxy-26,27-dipropylvitamin D3 were found to be much less active than 1,25-(OH)2D3 in a bone calcium mobilization test. 相似文献
72.
Simultaneous determination of keto and non-keto bile acids in human serum by gas chromatography with selected ion monitoring 总被引:2,自引:0,他引:2
A reliable method for the simultaneous determination of keto and non-keto bile acids in human serum was developed. Carbonyl substituents of bile acid ethyl esters were converted into methyloxime and hydroxyl substituents into dimethylethylsilyl ethers and the products were analysed directly by capillary gas chromatography with selected ion monitoring using [2H4]chenodeoxycholic and [2H4]3 alpha-hydroxy-7-oxo-5 beta-cholanoic acids as internal standards. The bile acid peaks on the selected ion chromatogram were separated without interference from endogenous substances present in serum. Recoveries of individual keto bile acids added to serum range from 74.4 to 94.7% with a mean of 87.1%. Eight kinds of keto bile acids not previously found in sera of normal subjects, namely 3-oxo-, 3-oxo-7 alpha-hydroxy-, 3-oxo-12 alpha-hydroxy-, 3 alpha-hydroxy-7-oxo, 3 alpha-hydroxy-12-oxo-, 3-oxo-7 alpha,12 alpha-dihydroxy-, 3 alpha,7 alpha-dihydroxy-12-oxo- and 3 alpha,12 alpha-dihydroxy-7-oxo-5 beta-cholanoic acids were identified and quantified. The total concentration of keto bile acids was found to be 0.16 +/- 0.08 nmol/ml and constituted 2.9 +/- 1.5% of that of the usual non-keto bile acids in peripheral venous serum. 相似文献
73.
Shizuko Eguchi 《Journal of mass spectrometry : JMS》1978,13(11):653-657
The mass spectra of 2,2-dimethylchromanones and 2,2-dimethyl-4-hydroxychromans show peaks corresponding to the ions formed by the retro Diels-Alder reaction with or without hydrogen transfer to the ion. The hydroxychromans also show peaks corresponding to an ion formed by the loss of hydrogen from the ion formed by the retro Diels-Alder reaction. Deuterium labelling showed that the hydrogen transferred in the chromanones arises from the gem-dimethyl groups on C-2, and the hydrogen atom lost in the case of the hydroxychromans is from C-4, the carbinyl carbon. 相似文献
74.
Miscibility and dehydration of poly(2-hydroxyethyl methacrylate) and poly(methacrylic acid) (PHEMA/PMAA) blends were investigated
by temperature modulated DSC (TMDSC), TG and solid-state 13C NMR methods. TMDSC spectra and 1H spin-relaxation times showed that the blends are homogeneous on a scale of 5-10 nm for all compositions. From TG and 13C NMR, we elucidated that the mass loss of the blends at 300°C is ascribed to the dehydration between the hydroxyl group of
PHEMA and the carboxyl group of PMAA.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
75.
76.
Dabdoub Paz Eduardo D. Santana Maria Helena A. Eguchi Silvia Y. 《Applied biochemistry and biotechnology》1993,39(1):455-466
Applied Biochemistry and Biotechnology - The addition of α-alumina to the aqueous solution of sodium alginate for imobilization of viable cells allows the production of denser particles than... 相似文献
77.
Araki T Eguchi K Enomoto S Furuno K Ichimura K Ikeda H Inoue K Ishihara K Iwamoto T Kawashima T Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Ogawa H Owada K Ricol JS Shimizu I Shirai J Suekane F Suzuki A Tada K Tajima O Tamae K Tsuda Y Watanabe H Busenitz J Classen T Djurcic Z Keefer G McKinny K Mei DM Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fu Y Fujikawa BK Goldman J Gray F Heeger KM Lesko KT Luk KB Murayama H Poon AW Steiner HM Winslow LA 《Physical review letters》2005,94(8):081801
We present results of a study of neutrino oscillation based on a 766 ton/year exposure of KamLAND to reactor antineutrinos. We observe 258 nu (e) candidate events with energies above 3.4 MeV compared to 365.2+/-23.7 events expected in the absence of neutrino oscillation. Accounting for 17.8+/-7.3 expected background events, the statistical significance for reactor nu (e) disappearance is 99.998%. The observed energy spectrum disagrees with the expected spectral shape in the absence of neutrino oscillation at 99.6% significance and prefers the distortion expected from nu (e) oscillation effects. A two-neutrino oscillation analysis of the KamLAND data gives Deltam(2)=7.9(+0.6)(-0.5)x10(-5) eV(2). A global analysis of data from KamLAND and solar-neutrino experiments yields Deltam(2)=7.9(+0.6)(-0.5)x10(-5) eV(2) and tan((2)theta=0.40(+0.10)(-0.07), the most precise determination to date. 相似文献
78.
Recent work on Euclidean self-dual gravitational fields is reviewed. We discuss various solutions to the Einstein equations and treat asymptotically locally Euclidean self-dual metrics in detail. These latter solutions have vanishing classical action and nontrivial topological invariants, and so may play a role in quantum gravity resembling that of the Yang-Mills instantons. 相似文献
79.
Thermal decomposition of N(phenylsulfonyl)-benzohydrazonoyl chloride (1) in refluxing toluene generated N-phenylsulfonylbenzonitrilimine (2) which gave 1,3-dipolar cycloadducts with ethyl (4a) and methyl acrylate (4b), acrylonitrile (4c), styrene (4d), norbornene (4e), and norbornadiene (4f). The reactions with 4a–d, 2 afforded regiospecifically 5-R substituted pyrazolines 5a–d in lower yields. The raction of 2 with 4e gave only exo adduct 5e, while the reaction with 4f gave both exo- (5fx) and endo adducts (5fn) as well as their retro-Diels-Alder product 6. 相似文献
80.